
<html>
  <head>
    <title>Hello World</title>
  </head>
  <style>
    body {
      background-image: linear-gradient(45deg, #ead790 0%, #ef8c53 100%);
      text-align: center;
    }
    button {
      background: rgba(0, 0, 0, 0.40);
      box-shadow: 0px 0px 4px 0px rgba(0, 0, 0, 0.5);
      border-radius: 8px;
      color: white;
      padding: 10px 20px;
      border: none;
      font-family: 'Roboto', sans-serif;
      font-size: 14px;
      position: relative;
      top: 40%;
      cursor: pointer;
      outline: none;
    }
    button:hover {
      background: rgba(0, 0, 0, 0.3);
    }
  </style>
  <body>
    <button onclick="sayHello()">Say Hello</button>
    <script type="text/javascript">
      function sayHello() {
        alert('Hello world');
      }
    </script>
  </body>
</html>